A kit-built, high-performance light plane crashed Monday in Central Oregon, killing two men, including one from Arlington Heights, the Deschutes County sheriff's office said.

The victims were identified as Harry Mortimer League, 68, of Arlington Heights and Patrick Franzen, 52, of Bend, Ore. Their bodies were recovered and their relatives have been notified, sheriff's Lt. Chad Davis said.

The plane was described as a single-engine Lancair IV-Propjet.

The cause of the crash was under investigation.

The Federal Aviation Administration initially said there were three people on board. An FAA spokesman did not immediately respond Monday night to an Associated Press call and email seeking comment.

The wreckage was spread over a large area near a logging road in the Deschutes National Forest about eight miles south of Sisters, Ore.

Sales director Doug Meyer said the Lancair IV-Propjet is a single-engine four-seater made from carbon fiber and capable of 350 mph. The model was designed in 1992 and there were about 600 sold as kits before it was replaced by another design several years ago.

Meyer said he spoke to a mountain biker who saw the crash and there was no obvious explanation for what witnesses have reported.

"Both pilots on board we are aware of were highly experienced professionals, not given to fool around," he said. "Something very strange happened. These airplanes don't come apart. They are very strong. They don't suffer inflight failures. The engines are very reliable. This is a very sophisticated airplane. When you have good experienced pilots they are very safe."

Meyer said the Propjet is considered an amateur-built experimental aircraft by the FAA and must be certified as airworthy before being allowed to fly.

Approximately 600 Lancair IV kits were produced by Lancair from 1991 through 2009 in three variants. Of those, approximately 70 were the "Propjet" turbo prop version. They are a four seat, pressurized, carbon fiber composite, high performance aircraft, a company spokesman told NBC Chicago.